Blood tests, explained
What each blood test measures, what a value outside the range can mean and what to ask next.
Low vitamin D: what your blood test result means and what to do nextLow vitamin D is very common in autumn and winter. What the 25-OH D test shows, which ranges labs use and what to ask your doctor next.
Low ferritin: what it means and what to ask nextFerritin shows your iron stores. What low or high ferritin can mean, why it can be low with normal haemoglobin and what to ask your doctor.
High TSH: what it says about your thyroid and which tests come nextA high TSH usually means your thyroid is working more slowly. How it is read next to FT4 and anti-TPO, what symptoms it can cause and what to ask your doctor.